Palm’s biggest consumer hit in years, the cute and cheap Centro, got some more love today when Palm announced they would be selling an unlocked GSM version (in white and gray, pictured) for $299. The Centro is also available on Verizon, Sprint, and AT&T for $99 or less with a contract.

In semi-unrelated news, the Centro’s version of Google Maps is getting an update. The new version, available for free starting today, adds My Location, which uses cell tower signals to approximate your position within about a kilometer on non-GPS phones. [Update: My Location currently works only on AT&T and Verizon Centros. Sprint Centro owners will have to wait for a software update coming later this summer.] As far as I know, Google Maps for Palm still does not include the public transportation features that were added recently for other platforms, but I’m crossing my fingers that it will be following soon.